Electric phonograph



Feb. 25, 1941. D Nom-QN ETAL 2,232,719

ELECTRIC PHONOGRAPH Filed Dec. 21, 1939 INVENTORS Leland J). Wn-on BYLucLas E vPerzLsczell v ORNEYS Patented Feb. 25, 1941 UNTED STATES PATENT OFFCE Pctruschell, Stratford, Conn.,

assignors to Dictaphone Corporation, New York, N. Y., a corporation of New York Application December 21, 1939, Serial No. 310,368

9 Claims.

This invention relates to electric phonographs and more particularly to electric remote control and power supply arrangement for such phonographs.

It is an object of this invention to provide an improved electric phonograph system and an arrangement Ior supplying electrical power to and remotely controlling the operation of such a phonograph.

It is a further object of this invention to provide a power supply system for electric phonographs adapted to supply all of the elements oi the electric phonograph circuit with electrical power at proper voltage, whether the phonograph be connected to a 11G-volt or a 220-volt power supply line, without the need for altering the electrical characteristic of the phonograph circuit elements.

It is also an object of this invention to provide such a power supply system in which a single fuse of low rating is so connected as to protect all of the circuit elements from damage due to overload, whether the system be connected to a llO-volt or a 22o-volt power supply circuit.

It should be noted that when reference is made herein to 11G-volt or 22o-volt power supply circuits, these figures are merely used for convenience in terminology, without intent to limit this invention to use with systems of these voltages only, inasmuch as this invention is equally applicable to use on power supply systems of voltages considerably different from these voltages but bearing approximately the same relationship to each other,

These and other apparent objects and advantages of this invention are obtained by the means described in the following specification and may be more readily understood by reference to the accompanying drawing which shows a schematic wiring-diagram of an electric phonograph power supply and control system embodying the invention.

Certain features of invention disclosed in this application are not claimed herein, but are described and claimed in a co-pending application,

Serial No. 348,768, iiled on July 31, 1940, the latter being a continuation-in-part oi the present application.

While this invention is applicable to any electrical system having a plurality of individual units requiring electrical power at predetermined voltages for satisfactory operation, for the purposes or" the present description it has been shown embodied in a multiple mandrel sound recording machine such, for example, as that shown in United States Patent No. 2,626,398. Such machines are well-known in the art and do not, per se, form any portion of the invention herein described. It is suliicient for the present description to state that such a machine comprises essentially a plurality of recording units, generally shown at I and I1, each having a record supporting mandrel, 2 and 3, rotatably mounted on suitable frames 4 and adapted to be rotated by 11G-volt driving motors 6 and 'l through suitable pulleys 8 and lo and belts i2. The motors 6 and l are connected through a single-pole double-throw switch I3 such, for example, as a mercury switch, to a suitable 11o-volt power source in the manner hereinafter to be described, so that either motor 6, motor l, or both motors may be operated by tilting the mercury switch I3, respectively, to the left (as shown in the drawing), to the right, or maintaining it in a horizontal position. Suitable recording units or cutting heads i4 and l5, such, for example, as those shown in United States Patent No. 2,057,621, are associated with each of the mandrels 2 and 3, respectively, and are adapted to cut sound tracks in cylindrical record blanks when such blanks are placed on these record supporting mandrels 2 and 3. These cutting heads I4 and l5 are mounted on suitable carriage structures (not shown) which are adapted to be driven across mandrels 2 and, 3 from left to right by means of feed screws (not shown) operated through suitable gears (not shown) from the pulleys ID. Recorder units I4 and l5 are connected to the output of a vacuum tube amplier 20, through a single-pole double-throw switch i6, which may be similar t0 switch I3. The input 22 of amplifier 2o is shown connected to a microphone 24, although it may be connected to any electrical source modulated by the sound to be recorded. The amplifier may be any suitable amplifying device having suiiicient amplifying ability and power output for the particular installation and it preferably includes a power supply rectifier and lter arrangement. Alternating current power is furnished to the anode potential portion of this amplifier unit through leads 26 from a secondary winding 28 of a power supply transformer, generally indicated at 3l), in the manner hereinafter to be described, and the heating current for the filaments or heaters of the vacuum tubes of the amplier unit 20 is supplied through leads from another secondary winding 32 of the transformer 3l).

When alternating current power is supplied to amplifier 2i! and to the circuit of motors 6 and 1, record blanks are placed on mandrels 2 and 3 and the cuttings heads I4 and I5 are placed in their initial or lefthand positions, the apparatus is ready to operate. As described in the above-mentioned United States Patent No. 2,026,398, mercury switches I3 and I6 are pivotally mounted in a linkage system so arranged that when mercury switches I3 and I6 are tilted to the left, as shown in the drawing, motor 6 and recorder I4 are connected, respectively, to the power supply and the output of the amplifier 20. With mercury switches I3 and I6 in this position, motor 6 will operate to rotate mandrel 2 and its associated record blank; and recording head I4, being connected through switch IB to the output of amplifier 20, will record a, sound track on this record blank corresponding to the sound impressed on microphone 24. When recorder I4 almost reaches the end of its path of travel along the record blank on mandrel 2, switches I3 and I6 are tilted until they assume a horizontal position. This connects motor I of machine II to the power supply in parallel with motor 8 and starts it operating to rotate mandrel 3 and its associated record blank. At the same time, recorder I5 is connected in parallel with recorded I4 across the output of amplier 20 and starts traversing the record blank on mandrel 3 to start the recording thereon before the recording on mandrel 2 is ended, thus providing a slight overlap in the recording being made on these two blanks. As recorder I4 progresses further along the record blank on mandrel 2 to the end of the travel, it further actuates the linkage mechanism associated with mercury switches I3 and I6 to tilt them to the right, thus disconnecting motor E from the power supply and recorder I4 from the output I8 of the amplier 20, thereby ending the recording on mandrel 2 of machine I. If the recorded blank on mandrel 2 is replaced by a fresh blank and recorder I4 is moved to its initial position at the left-hand end of mandrel 2, the sequence of operation just described will be repeated in a reverse direction, with mercury switches I3 and I6 being tilted iirst to horizontal position and then to a left-hand tilted position as recorder head I5 approaches the end of its travel, thus providing a slight overlap in recording on the end of the record blank on mandrel 3 and the start of the record blank on mandrel 2. With this arrangement, by constantly supplying fresh record blanks to the mandrels 2 and 3 as each precedent blank is filled with a sound groove, a continuous recording can be made of any sound impinging on microphone 24. The apparatus thus far described is substantially the same as that disclosed in the above-mentioned United States Patent No. 2,026,398.

Apparatus of this type is frequently used for recording lengthy conferences, conventions, speeches, telephone conversations, etc., and it is therefore frequently desirable to have the microphone at some distance from the recording machine and to provide means for remotely controlling the operation of the machine at the microphone. Such an arrangement also permits the attendant who changes the records on the mandrels 2 and 3 to be in another room remote from the microphone.

In the embodiment shown in the drawing, such remote control is effected by providing a remote control box, generally indicated at 34, connected by a seven-wire cable, generally indicated at 35. to the rest of the apparatus. The control of electric power.

box 34 is provided with a main power supply or standby switch 38 for connecting the machine to the power supply circuit to put it in condition for operation; and an operating or start and stop switch 43, which is operated by the dictator or speaker whenever he wishes to start or stop the recording action of the apparatus. The control box 34 is also equipped with three suitable indicator lights 42, 44, and 4G. Light 42 is a standby lamp which lights whenever standby switch 38 is closed to indicate that the apparatus .is ready to operate. Lights 44 and 45 are connected, respectively, with recording machines I and II to indicate when either of these machines is in operation, i. e., when the recorder heads I4 and I5 are away from their initial or left-hand positions. Indicating lights 48 and 59 are provided at the recording machines I and II to inform the attendant of the condition of the apparatus, light 50 indicating that the apparatus is in standby condition, and light 48 indicating to the attendant that the motor circuit either to motor B or I is closed and therefore that either machine I or II is actually operating. Further, a relay, generally indicated at 52, is provided to close the plate circuits of the ampliiier 2U and to close the circuit to motors 6 and 'I whenever the operating switch 40 is in start or operating position, and to open these circuits whenever the operator wishes to stop recording.

Indicating lamps 44 and 45 are operated by switches mounted on machines I and II and shown diagrammatically in the drawing at 54 and 56, respectively. These switches 54 and 56 are comprised essentially of lever arms 58 pivoted on the frames 4 to position contacts 63 and 52 to make or break electrical circuits through indicating lamps 44 and 46. Springs 64 hold these contacts in normally closed position. The upper ends of levers 58 are positioned so as to be moved by the recorder units I4 and I5 when they are moved to their initial or extreme left-hand positions (as illustrated by the position of recorder unit I5 in the drawing) to open the circuits between contacts G and 62, thus breaking the circuits to the indicating lamps 44 and 46.

If such an instrument is always to be operated in the same place on a fixed power supply line voltage, all of the various elements of the system, i. e., the motors 6 and 1, the attendant motor operating indicating light 48, the readyto-operate or standby lights 50 and 42, the individual mandrel operating lights 44 and 46, the primary of the amplifier power supply transformer 30, and the solenoid oi the relay 52, would be connected in parallel across the power supply line in series with a fuse. This is not always the case, however. Recorders of this type frequently must be carried from place to place and are often made up in portable form for this purpose. Such portability requires adaptability to operation on any conveniently available source Under these conditions, operation on power supply lines with widely diierent line voltages is frequently necessary. There is considerable use of both volts and 220 volts as standard line voltage. In order to provide satisfactory portable apparatus of this nature, it is desirable, therefore, that such apparatus be adaptable to operation on 1l0-volt or 220-volt power supply lines with a minimum of alteration in circuits and circuit elements.

In accordance with this invention, this is accomplished by connecting all of the circuit eler ments of the electric phonograph in the manner shown in the drawing. Power supply transformer 38 is provided with two electrically equivalent windings 66 and 68. These windings are so designed that when either is connected across 110- volt power supply as a primary winding the plate supply secondary winding 28 and the filament supply secondary winding 32 develop the correct voltages required by the amplier 28 for satisfactory operation. These two windings 66 and 68 are connected in series through a fuse 18. One end of winding 66 is connected through main power supply switch 38 to one side of the plug l2 adapted to be connected tothe available power supply outlet. The other terminal of the power supply plug 'I2 is connected through a single-pole double-throw switch 14 to one end or the other of the other primary winding 68, depending upon Whether the machine is to be connected to a 110-volt or 22o-volt power supply.

With this arrangement, when 110-volt operation is desired, the arm of switch 14 is moved to contact 16, thus connecting winding 66 in series with fuse 'I8 across the 110-volt supply line to act as the primary of the transformer 38. Winding 68 thus becomes an effective secondary winding. For 22o-volt operation the arm of switch 'I4 is placed on Contact 18, thus connecting wind.. ings 66 and 68 in series, with the fuse 10 connected therebetween, to effectively form a single 220vclt primary winding for connection to a 22o-volt power supply. In either case, with the switch 'I4 properly positioned, dependent upon the voltage of the power supply to which terminal plug 'I2 is connected, the secondary windings 528 and 32 of the transformer 30 will develop the voltage necessary for proper operation of amplifier 28, and in both cases these secondary windings will be protected by the fuse Ill from overload.

Solenoid 88 of relay 52 is connected in series with start and stop switch 40 across primary winding 66. When this solenoid is energized by the closing of switch 40, it closes two pairs of contacts 82 and B4.

Contacts 82 are connected in series with a circuit including motors 6 and '1, mercury switch I3, motor operating light 48, and with fuse 'l0 across primary winding 66. Thus contacts 82, operating in response to energization and deenergization of solenoid 80 caused by closing and opening start and stop switch 40, control the starting and stopping of motor 6 or 1, depending upon the position of mercury switch I3, and the operation of signal light 48. It is readily apparent that, when the apparatus is conditioned for operation on 110 volts by moving switch 'I4 to contact T6, motors 6 and 1 and control light 48 which are 110 volt operated elements, are connected directly -across the 110-volt line. When the apparatus is conditioned for operating on 220 volts by moving the contact arm of switch "F4 to contact 18, these 110-volt elements are connected across winding 66 which then acts as the K' secondary portion of a 22o-volt auto-transformer,

.longing the life of the electronic tubes in the ampliner.

The 110-volt ready-to-operate or standby signal lamp 42 in the remote control box 34, and the corresponding lamp 50 mounted at the machine, are connected in parallel across winding 68. Onr 110-volt operation this winding 68 acts as a 110-volt secondary winding coupled to the primary winding 66 and provides 110 volts for operating these signal lamps whenever the primary 68 is energized, to indicate that the machine is in standby condition. On 220-volt operation, when winding 68 acts as one-half of the primary winding of the transformer, the signal lamps 42 and 50 lare operated by the 110 volts developed acrossv -this winding acting asa secondary portion of an auto-transformer, and similarly indicate that the machine is in standby condition.

The 110-volt signal lamps 44 and 46 in the remote control box 34, which indicate which of the two recording heads I4 or I5 is in operation, are connected in series with their respective switch 58 and 56 across winding 66 and fuse 10. Thus,

these lamps are connected in parallel with the motors 6 and 1 and the motor operating signal lamp 48, so that, as above-mentioned, they are connected directly across the 110-volt line when the apparatus is conditioned for 110-volt operation, and across winding 66 acting as the 110- i volt secondary of an auto-transformer when the apparatus is conditioned for operation on 220 volts.

summarizing the above description, when the apparatus is conditioned for operation on 110 volts, winding 66 acts as a primary winding, winding 28 acts as a secondary winding to deliver plate voltage to amplifier 20, winding 32 acts as a secondary to deliver filaments or heater voltage to amplier 20, and winding 68 acts as a secondary to deliver 110 volts to signal lamps 50 and 42. In addition, motors 6 or 1, indicating lamps 44, 46, and 48, and solenoid coil 80 are connected directly across the 110-volt power supply. When the apparatus is conditioned for 220- volt operation, windings 66 and 68 are connected in series through fuse 10 and act as a primary winding, windings 28 and 32 still act as secondary windings delivering the same voltage as under 110-volt operation to the plates and filaments of amplier because the primary still develops the same number of ampere-turns as before. Winding 66 acts as the secondary winding of an auto-transformer to deliver 110 volts tosolenoid 80, indicator lamps 44, 46, and 48, and motors 6 or 1; and winding 68 acts as the secondary of an auto-transformer to deliver 110 volts to signal lamps 42 and 58.

Therefore, it is evident that with the apparatus connected as above described, although the electric phonograph circuit is composed of a plurality of circuit elements each requiring a 110- volt power supply for proper operation, it is capable of operating on either 110-volt or 22o-volt power supply lines without altering the electrical characteristics of any of the circuit elements by merely moving the arm of single-pole doublethrow switch 'I4 from contact switch 16 to contact 18.

Furthermore, with a machine embodying the invention as above described, the circuit arrangement is such that with the single fuse 'I0 connected between the windings 66 and 68 it can be used to protect all of the elements of the system against damage whether the machine be conditioned for or 220-volt operation. For example, on 110-volt operation the loads on the fuse I8 are secondary 28 and 32, relay solenoid 80, and winding 68 acting as a secondary. Under these conditions, motors 6, 1, and signal lamps M, 4B, and 48 are not fused. However, if the machine is subjected to a voltage suilicient to cause the fuse 10 to blow, these circuit elements 10 will be protected because the relay solenoid is fused and will be instantly deenergized, thus opening the circuit to these elements. When the apparatus is connected for 22o-volt operation, the current through the fuse due to the load on secondaries 2B, 32 and windings 66 and 68 acting as auto-transformer secondaries, is considerably decreased, and therefore, although the circuits of motors 6 or 1 and signal lamps 44, 48, and 48 are now connected in the fuse circuit, the normal operating current through the fuse is still maintained at a suiciently low value so that the fuse used on 110-volt operation is still adequate to protect the circuit elements for 220-volt operation.

I claim:

1. An electric phonograph power supply for supplying power to a plurality of load elements of an electric phonograph each of which requires power at a certain predetermined voltage for sat isfactory operation, comprising, in combination. a transformer having a first and second winding, said rst winding being adapted to be connected across an electrical power source of a first predetermined voltage las a primary winding and serving as a secondary to supply electrical power to certain of said load elements at said first predetermined voltage, said second winding serving as a secondary to said first winding to supply the remainder of said load elements with electrical power at a second predetermined voltage, means for connecting said first and second windings to form a primary adapted to be connected across a power source having a voltage equal to the sum of said first and second predetermined voltages, said iirst and second windings also serving as secondary windings to supply power to said load elements at said first and second predetermined voltages respectively whereby all of said load elements are supplied with power at said predetermined voltages whether said phonograph is supplied with power at said iirst predetermined voltage or at a voltage equal to the sum of said iirst and second predetermined voltage.

2. An electrical phonograph power supply for supplying' power to a plurality of load elements of an electric phonograph each of which requires power at a predetermined voltage for satisfactory operation, comprising, in combination, a transformer having a rst and second winding, said first winding being adapted to be connected across an electrical power source of said predetermined voltage as a primary winding and serving as a secondary to supply electrical power to certain of said load elements at said predetermined voltage, said second winding serving as a secondary to said first winding to supply the remainder of said load elements with electrical power at said predetermined voltage, means for connecting said iirst and second windings to form a primary adapted to be connected across a power source having a voltage approximately double said predetermined voltage, said first and second windings also serving as secondary windings to supply power to said load elements at said predetermined voltage whereby all of ,said load elements are supplied with power at said predetermined voltage whether said phonograph is supplied with power at said predetermined voltage or at a voltage equal to approximately double said predetermined voltage.

3, An electrical phonograph power supply for supplying power to an electric phonograph circuit including a plurality of load elements requiring power at a voltage of approximately 110 volts for satisfactory operation, comprising, in combination, a transformer having a iirst 110-volt primary winding and a second 110-volt primary winding, said windings being connected in series, power supply terminals, means for connecting said terminals across said first primary winding when said phonograph is to be operated from a 110-volt power supply and for connecting said terminals across both of said primary windings in series when said system is to be operated from a 22o-volt power supply, certain of 110-volt load elements being connected across said first primary winding, the remainder of said 110-volt load elements being connected across said second primary winding whereby all of said load elements are supplied with power at 110 volts whether said phonograph is connected to a l10- volt or a 220-volt power supply.

4. In an electric phonograph adapted to be operated on 110-volt or 220-volt power supply circuits and having all of its load elements adapted to operate on 110 volts, a power supply, comprising, in combination, a power transformer having a first 110-volt primary winding and a second 110-volt primary winding, said iirst and second primary windings being connected in series, power supply terminals, means for connecting said power supply terminals across said first primary winding to adapt said system lor 110-volt operation and across both of said primary windings connected in series to adapt said system for operation on 220 volts whereby all of the 110- volt operated load elements of said phonograph are supplied with power at the proper voltage whether said phonograph is connected to a 110- volt or a 220-Volt power supply.

5. An electric phonograph power supply for supplying power to a plurality of load elements of an electric phonograph circuit each of which requires power at a predetermined voltage for satisfactory operation, comprising, in combination, a transformer having a rst and second winding, said first winding being adapted to be connected across an electrical power source of said predetermined voltage as a primary winding and serving as a secondary to supply electrical power to certain of said load elements at said predetermined Voltage, said second winding serving as a secondary to said iirst winding to supply the remainder of said load elements with electrical power at said predetermined voltage, means for connecting said iirst and second wind ings to form a primary adapted to be connected across a power source having a voltage substantialiy greater than said predetermined voltage, said first and second windings also serving as secondary windings to supply power to said load elements at said predetermined voltage whereby all of said load elements are supplied with power at said predetermined voltage whether said phonograph is supplied with power at said predetermined voltage or at said substantially greater voltage.

6. An electric phonograph power supply for supplying power to a ,plurality of load elements of an electric phonograph circuit each of which requires electric power at a predetermined voltage for satisfactory operation, comprising, in combination, :a transformer having a rst and second winding, saiid rst winding being adapted to be connected across an electrical power source of a rst predetermined voltage as a primary winding and serving as .a secondary to supply electrical power to certain of said load elements at said rst predetermined voltage, said second winding serving .as a secondary to said rst winding to supply the remainder of said load elements with electrical power ata second predeteermined voltage, means for connecting said iirst and second windings to form a primary .adapted to be connected across a power source having a voltage substantially greater than said first predetermined voltage, said first and second windings also serving as secondary windings to supply power .to certain of said lroad elements at said first and second predetermined voltages, respectively, whereby all of said load elements are supplied with power iat said predetermined voltages whether said phonograph is supplied with power at said first predetermined voltage or at said substantially greater voltage.

7. An electric phonograph power supply for supplying power to a plurality :oi circuit elements of an electric phonograph, comprising, in combination, a transformer having a first and second winding, said windings being adapted to be connected across an `electrical power source to act as primaries and being adapted to serve as secondaries with respect to each yother to supply electrical power to certain of said circ-uit elements connected across each of said windings respectively, fuse means, said fuse means being connected in series between said rst and second windings, means connecting one side of said power supply line with one end of said first winding, and means for connecting the other side of said power supply line to either end of said second winding to adapt the elect-ric phonograph for operation on power supply lines of different voltages, the various circuit elements of said electric phonograph being so apportioned between said iirst winding and said second winding that fuse means of a single rating is adequate to protect all the elements of said phonograph circuit whether a power supply line is connected to .one end or the other of said second winding.

8. An electric phonograph power supply for supplying power to a plurality of circuit elements of an electric phonograph, comprising, in combination, a transformer having a first and second winding and at least one other secondary winding having certain circuit elements connected thereacross, said iirst and second windings being adapted to be connected across an electric-al power source to act as primaries and being adapted to serve as secondary windings with respect to each other and to said secondary winding to supply electrical power to certain of said circuit elements connected across said first and second windings respectively, fuse mean-s, said fuse means being connected in series between said rst and second windings, means connecting one side of said power supply line with one end of said first winding, and means for connecting the other side of said power supply line to either end of said second winding to adapt the electric phonograph for operation on power supply lines of different voltages, the various circuit elem-ents of said electric phonograph being so apportioned between said iirst winding, said second winding and said secondary winding that fuse means of a single rating is adequate to protect ail the elements of said phonograph :circuit whether a power supply line is connected to one end or the other of said second winding.

9. An electric phonograph power supply for supplying power to a plurality of circuit elements of an electric phonograph, comprising, in combination, a transformer having a iirst `and second winding, said windings being adapted to be connected across an electrical :power source to serve as ,primary windings and being adapted to serve as secondary windings with respect to each other to supply electrical power to certain of said circuit elements connected across each of said windings respectively, f-use means, said fuse means being connected in series between said iirst and second windings, means connecting one side of sai-d power supply line with one end of said iirst winding, means for connecting the other side of said power supply line to either end of said second winding to adapt the electrical phonograph for operation on rpower supply lines of different voltages, various circuit elements of said electrical phonograph being so apportioned between said first winding and said second winding that fuse means of a single rating is adequate to protect all elements in said phonograph circuit whether a power supply line is connected to one end or the other of said second winding, relay means comprising energizing means and circuit control means, said circuit elements connected across said iirst or second windings including said re- 'lay energizing means, and said circuit control means of said relay being connected in a circuit connecting certain other of said phonograph circuit elements directly to said power supply line whereby said latter elements yare automatically disconnected from said power supply line when said fuse means operates.

LELAND D. NORTON. f LUCIUS P. PET-RUSCHELL. 

